The movement is the heart of a custom watch — it decides how many subdials you can have, whether you get a date or a GMT hand, and how thick the finished watch will be. Here's how the most popular, buildable calibers stack up, and what each one is best for. Design around any of them in the free watch builder, which maps your layout to a real movement automatically.
| Caliber | Type | Subdials | Date | ~Thickness | Best for | Buy |
|---|---|---|---|---|---|---|
| Seiko NH35 | Automatic 3-hand | 0 | Yes | 5.3 mm | Divers, field | Buy › |
| ETA 2824-2 | Automatic 3-hand | 0 | Yes | 4.6 mm | All-round Swiss | Buy › |
| Sellita SW200 | Automatic 3-hand | 0 | Yes | 4.6 mm | 2824 alternative | Buy › |
| Miyota 9015 | Automatic 3-hand (thin) | 0 | Yes | 3.9 mm | Dress watches | Buy › |
| Seagull ST19 | Hand-wound chronograph | 2 | No | 6.7 mm | Bi-compax chronos | Buy › |
| Valjoux 7750 | Automatic chronograph | 3 | Yes | 7.9 mm | Pilot & racing chronos | Buy › |
| ETA 2893-2 | Automatic GMT | 0 | Yes | 4.1 mm | GMT / travel | Buy › |
Want a simple, tough watch? A Seiko NH35 or ETA 2824-2 three-hander is the easiest first build. Going slim and dressy? The Miyota 9015 keeps the case thin. Chasing a chronograph? Two subdials point to the Seagull ST19; three subdials plus a date mean the Valjoux 7750. Traveling? The ETA 2893-2 drives a true GMT hand. The builder's compatibility engine picks the right one for your layout and warns you if a combination — like a GMT hand with chronograph subdials — can't be built off the shelf.
Design a watch around your movement →More reading: how to build your own watch · popular builds